This core has two main functions: a) to help evaluate the materials that are intended for clinical studies, in a number of model systems, using the advanced animal imaging instrumentation available at the COH; and b) the analysis of clinical blood, urine, bone marrow, and tissue biopsy samples. The Specific Functions are: 1) To provide the needed facilities and expertise for evaluating the biodistribution and imaging cells and antibody constructs in small animals, and 2) To perform core studies on clinical samples obtained from patients entered on imaging and therapy trials. This Core is a critical component. All antibody and T-cell constructs will be evaluated in vitro and in vivo prior to translation into the clinic. The in vivo analysis will be performed as part of this Core using the expertise of the Core's personnel. Animal biodistribution and imaging studies will be performed using the Core personnel with help as needed from the individual projects. Luciferase transfected tumor cell lines and T-cells will be generated as part of the projects and antibodies and their engineered constructs will be radiolabeled as part of the individual projects. The in vivo studies will be performed in the City of Hope Animal Resource Center in the Parvin building. The City of Hope National Medical Center and Beckman Research institute is developing an animal imaging facility. It has a Xenogen in vivo biophotonic imaging system (IVIS) and has recently accepted delivery of a Biospace Instruments animal gamma scintillation camera. A Concorde Microsystems microPET@/ R4 for small animals imaging has been ordered; it is due to be delivered in June 2003. This core will also analyze clinical samples from patients participating in the clinical trials. Analysis of blood and urine samples to determine the pharmacodynamics of the radiolabeled antibodies and their engineered constructs will be performed by this Core. Samples will be counted to determine the pharmacokinetics and selected samples will be analyzed by high performance liquid chromatography to evaluate the status of the labeled construct. In vitro assays to determine circulating levels of infused antibodies and constructs, as well as their immunogenicity, will also be performed by this Core.. Immunoassays will be performed by ELISA or using methods developed using the PerkinEImer VICTOR plate reader using time-resolved fluorometry.